Patent US3980445A successfully refreshed from Google Patents.
US3980445A
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Method of making filtering metal material
Assignee: Individual
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Filing: 1974-07-03
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Granted: 1976-09-14
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Expires: 1994-07-03
Abstract
Abstract A method of making filtering material from powdered steel whereby said powdered steel is cold rolled into strip and the latter undergoes a two-stage sintering process. The material produced by this method is intended for filtering fluids such as liquid fuel or brake fluid and is capable of retaining mechanical particles of the order of 2-3 microns.
Inventors
- 👤 Vasily Alexeevich Aleshin
- 👤 Galina Petrovna Bazarova
- 👤 Serafima Pavlovna Gromova
- 👤 Jury Iosifovich Dmitriev
- 👤 Jury Arkadievich Kuteminsky
- 👤 Iza Ivanovna Komolova
- 👤 Georgy Olegovich Leschinsky
- 👤 Vsevolod Konstantinovich Sorokin
- 👤 Galina Ivanovna Sazonova
- 👤 Alexandr Fedorovich Silaev
- 👤 Grigory Fedorovich Tikhonov
- 👤 Valery Mikhailovich Schekin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:36
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/10; B22F3/11; B01; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2027; B01D39/2031; B01D39/2034; B22F3/18; B22F2998/00; B22F2998/10; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/923; Y10S428/924; Y10S428/926; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12153; Y10T428/12479
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
131 words
A method of making filtering metal material whereby powdered austenitic stainless steel ground into particles 10 to 30 microns is cold rolled to a strip form by being passed between mill rolls spaced 0.08 to 0.12 mm apart and rotating at a speed of 2 to 4 revolutions per minute, the strip material so produced undergoing a two-stage sintering process wherein the first stage of sintering is carried out in a reducing atmosphere at a temperature of 820° to 880°C for 2 to 3 hours and is followed by cooling down to 100°C in a reducing atmosphere and the second stage of sintering is carried out in a reducing atmosphere at a temperature of 1100° to 1150°C for 2 to 4 hours and is followed by cooling in a reducing atmosphere.
Claim 2
Independent Claim
131 words
A method of making filtering metal material whereby powdered austenitic stainless steel ground into particles 10 to 30 microns is cold rolled to a strip form by being passed between mill rolls spaced 0.08 to 0.12 mm apart and rotating at a speed of 2 to 4 revolutions per minute, the strip material so produced undergoing a two-stage sintering process wherein the first stage of sintering is carried out in a reducing atmosphere at a temperature of 820° to 880°C for 2 to 3 hours and is followed by cooling down to 100°C in a reducing atmosphere and the second stage of sintering is carried out in a reducing atmosphere at a temperature of 1100° to 1150°C for 2 to 4 hours and is followed by cooling in a reducing atmosphere.
Claim 3
Dependent Claim
84 words
A filtering metal material consisting essentially of powdered austenitic stainless steel ground into particles 10 to 30 microns with interstitial spacing sufficient to retain particles of the size of 2-3 microns at elevated temperatures of up to 600°C, said material being cold rolled to a strip form by being passed between mill rolls and having a filtering capacity of 0.004-0.006 1/cm 2 /min., a tensile strength of 11-13.5 kg/cm 2 , a strip thickness of 0.15-0.18 mm., and a porosity ranging from 25-30 percent.
Claim 4
Dependent Claim
84 words
A filtering metal material consisting essentially of powdered austenitic stainless steel ground into particles 10 to 30 microns with interstitial spacing sufficient to retain particles of the size of 2-3 microns at elevated temperatures of up to 600°C, said material being cold rolled to a strip form by being passed between mill rolls and having a filtering capacity of 0.004-0.006 1/cm 2 /min., a tensile strength of 11-13.5 kg/cm 2 , a strip thickness of 0.15-0.18 mm., and a porosity ranging from 25-30 percent.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-14 | 1980-03-15 | 1980-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-14 | 1984-03-15 | 1984-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-14 | 1988-03-15 | 1988-09-14 | $7700.00 | Window Closed / Lapsed |